/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8                               :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ Permission to use, copy, modify, and/or distribute this software for         │
│ any purpose with or without fee is hereby granted, provided that the         │
│ above copyright notice and this permission notice appear in all copies.      │
│                                                                              │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
│ PERFORMANCE OF THIS SOFTWARE.                                                │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/syscall-sysv.internal.h"
#include "libc/calls/syscall_support-sysv.internal.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/errfuns.h"

int32_t sys_pipe2(int pipefd[hasatleast 2], unsigned flags) {
  int e, rc;
  if (!flags)
    goto OldSkool;

  int flags2 = 0;
  if (IsLinux()) {
    flags2 = flags;
  } else {
    flags2 = flags & O_ACCMODE;
    if (flags & O_NONBLOCK)
      flags2 |= 4;
    if (flags & O_DIRECT) {
      if (IsFreebsd()) {
        flags2 |= 0x00010000;
      } else if (IsNetbsd()) {
        flags2 |= 0x00080000;
      } else {
        return einval();
      }
    }
    if (flags & O_CLOEXEC) {
      if (IsXnu()) {
        flags2 |= 0x01000000;
      } else if (IsFreebsd()) {
        flags2 |= 0x00100000;
      } else if (IsOpenbsd()) {
        flags2 |= 0x00010000;
      } else if (IsNetbsd()) {
        flags2 |= 0x00400000;
      } else {
        return einval();
      }
    }
  }

  e = errno;
  rc = __sys_pipe2(pipefd, flags2);
  if (rc == -1 && errno == ENOSYS) {
    errno = e;
  OldSkool:
    if ((rc = sys_pipe(pipefd)) != -1) {
      if (flags) {
        __fixupnewfd(pipefd[0], flags);
        __fixupnewfd(pipefd[1], flags);
      }
    }
  }
  return rc;
}
